October is quickly approaching and is one of the most important months for your lawn. During that time, we typically see the temperatures cool off causing slower grass growth. A weak turf is much more susceptible to winter damage and is much slower to recover in the spring. So, now through mid-October is the best time to fertilize. If you only fertilize only once a year, this is the time to do it. Of course, there are a few other little chores to consider.
I would suggest using a fertilizer that has a minimum of ½ of the nitrogen in a slow release form. Even better if the fertilizer is mostly slow release. This information it located on the fertilizer bag. Just remember not to apply more than 1 pound of actual nitrogen per year. Or, if you want to know exactly how much fertilizer to put out, have a soil test performed. You can call our office at 936-539-7824 and we can point you in the right direction for that. Lower nitrogen rates that are in the slow release form will provide fertility over a long period of time. The result will be an even growth rate while reducing nitrogen run off and fungal problems. Be sure to check the recommended method of application on the label and take a few minutes to measure your yard so you know how much area you are treating. Most people will find that they have better results using lower amounts of fertilizer rather than too much.
Most annual grasses and weeds that plague lawns in late winter and early spring begin to germinate in October and into November depending on our weather. The best way to stop them in the lawn is to apply a pre-emergent herbicide before the weed seeds start to germinate in October. Of course, if you do not have or experience a high number of weeds in the winter then it is not necessary to use a pre-emergent. Pre-emergent herbicides are chemicals that kill weed seedlings as they germinate. They are ineffective once weeds grow beyond the seedling stage. They should be applied according to the label in a uniform broadcast treatment, followed by at least 1/2 inch of irrigation to move the product into the soil where it is activated.
Post-emergent herbicides are used for weeds which have already emerged. Those can be used later in case you end up missing the boat on a pre-emergent application. Also, be careful not to get herbicides on desirable flowers, shrubs, etc. The chemicals do not know the difference between a weed and a broadleaf ornamental! Most important, read the label first before using the product.
Some people like to over-seed their lawns for year-round green color. Over-seeding should be done from mid-Oct through November using annual or perennial ryegrass. A mix of the two works well also. Plant the seeds at a rate of 5# per 1,000 square feet of lawn. Over-seeding is generally not recommended on St. Augustine lawns. It competes with the grass for sunlight, nutrients and water making it slow to recover in the spring. If your turf is stressed or weak, I would avoid over-seeding because it will only make the problem worse.
Lastly, as we move further into the fall, we will likely see flare-ups of Large Patch (aka Brown Patch). The fungus is present year-round. However, we only see the symptoms under certain conditions. The fungus survives through the summer heat and then begins to thrive as temperatures ease in the Fall and Spring (70 degrees of below) and under wet conditions. If you have had this issue before, it is imperative to stay away from high nitrogen fertilizers and reduce your irrigation. I use the analogy that using high nitrogen fertilizers on your lawn in the fall “is like throwing gasoline on a fire”. The is only make the growth of the fungus accelerate and spread quickly. Low lying areas tend to be more susceptible to Large Patch. Consider adding about ½ inch of a sandy loam or a compost to the low areas to improve drainage and level them out with the rest of the yard. Adding more than the ½ inch of soil can smother the grass kill it. Hopefully these tips will help strengthen your lawn and keep you worry free in the future.
Don’t forget to send your garden questions to Plant Answers at 9020 Airport Rd., Conroe TX 77303 or e-mail me at mpot[email protected]